Aiptasia?

[Brian E]

I see threads from a spaghetti worm moving around. I don't see an aiptasia in the video. That doesn't mean there isn't one there.
A stalk with a disk on the end with arms radiating from it. They always look like this.
Turn on your sink hat water asn let it get as hot as it can and them turn is down to a trickle and let it hit the spot to 30 seconds. Scrub it with a toothbrush and repeat once.

I looked up pictures of spaghetti worm. Looks like that's what it is!

 

[Brian E]

For anyone following. Here's a better video before I eradicate it

.

 

[afrokobe]

For anyone following. Here's a better video before I eradicate it

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definitely not an aiptasia, but I have no idea what that is lol

 

[Just John]

See what others say, but I wouldn't bother to get rid of it unless it is bothering the coral. Most people have them in their tanks, but usually in the sand.

 

[vetteguy53081]

Looks to me as a spaghetti worm.
Best bet:
Take frag out and place in a container of tank water. Inspect underneath. If indeed aptasia, you can scrape it off as well as it is hydroid or tube worm.
Spaghetti worm will look like this:

 

[Tamberav]

I would consider a spaghetti worm beneficial. It would probably love to move to your sandbed and help keep it clean.

 

[WVNed]

Honestly I don't know if a spaghetti worm is beneficial or not. Things like it are exactly why I have marine tanks though.
I love watching interesting things from the sea do their thing. You can buy corals in 1000 stores. Go try to buy the 100s of little things that should live in your tank too under and around them.
Go to a dollar store and buy some magnifying reading glasses. Very nice to look at small things with your hands free.
Look at your tank with a flashlight after it's been dark for a couple of hours.